CH. 16 - MOLECULAR GENETICS QUESTIONS 1. Briefly describe Griffith's experiments with Streptococcus pneumoniae which led to early information about the genetic material and transformation. 2. Briefly describe how Watson and Crick came to the discovery of the double helix structure of DNA. 3. What are Charglaff's rules? What organisms obey these rules? 4. Diagram the basic structure of a nucleotide. Identify the carbon atoms in your diagram(use 1' to 5'). 5. Diagram a purine and a pyrimidine. 6. What purines and what pyrimidines are found in DNA? 7. Diagram a small strand of DNA showing the hydrogen bonds between A-T and C-G. 8. Draw a section of DNA showing the double helix structure. 9. What is meant when we say that the two strands of DNA are "antiparallel"? 10. Can DNA be made without a "template" of previously existing DNA? 11. What is semiconservative replication? Describe how DNA is replicated semiconservatively. 12. Are Okazaki fragments parts of ground up Japanese biologists? If not what are they? 13. In which direction is DNA copied? (3' to 5' or 5' to 3') !1 14. What is DNA "proofreading"? Does it work very well or are there alot of misteaks that creap throug? 15. What do each of the following enzymes do? DNA gyrase "rep" or DNA helicase DNA polymerases DNA ligase 16. Complete the chart comparing DNA and RNA: DNA RNA # OF STRANDS TYPE OF SUGAR PURINES PYRIMIDINES WHERE FOUND IN CELL? !2